“3GPP (3rd Generation Partnership Project)” is a project that studies and creates a specification of a portable telephone system that is based on a network formed by developing W-CDMA (Wideband-Code Division Multiple Access) and GSM (Global System for Mobile Communications).
In 3GPP, a W-CDMA scheme is standardized as a third generation cellular mobile communication system and its services are being sequentially started. HSDPA (High-Speed Downlink Packet Access) whose communication speed is further increased is also standardized and its services are also being started.
In 3GPP, consideration is advancing on a mobile communication system (hereinafter, referred to as “LTE-A (Long Term Evolution-Advanced)” or “Advanced-EUTRA”) that realizes transmission and reception of data at a further higher speed by utilizing the evolution of the third generation wireless access technology (referred to as “LTE (Long Term Evolution) or EUTRA (Evolved Universal Terrestrial Radio Access)) and a system bandwidth that is further wider.
An OFDMA (Orthogonal Frequency Division Multiple Access) system has been proposed that executes multiplexes users using subcarriers that are orthogonal to each other, as a downlink communication system in EUTRA.
The OFDMA system employs techniques such as an adaptive modulation/demodulation and error correction scheme (AMCS: Adaptive Modulation and Coding Scheme) that is based on adaptive radio link control (Link Adaptation) such as channel coding.
“AMCS” is a scheme that switches between wireless transmission parameters (also referred to as “AMC mode”) such as an error-correcting system, the coding rate of the error correction, and the data modulation multiple-value number due to the channel quality of each mobile station apparatus in order to efficiently execute a high speed packet data transmission.
The channel quality of each mobile station apparatus is fed back to a base station apparatus using CQI (Channel Quality Indicator).
FIG. 12 is a diagram of the channel configuration that is used in a conventional wireless communication system. The channel configuration is used in a wireless communication system such as EUTRA (see Non-Patent Literature 1). The wireless communication system depicted in FIG. 12 includes a base station apparatus 100 and mobile station apparatuses 200a, 200b, and 200c. “R01” denotes the coverage area of the base station apparatus 100 and the base station apparatus 100 communicates with the mobile station apparatuses that are present in the coverage R01.
In EUTRA, in a downlink to transmit a signal from the base station apparatus 100 to the mobile station apparatuses 200a to 200c, a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical multicast channel (PMCH), a physical control format indicator channel (PCFICH), and a physical hybrid ARQ indicator channel (PHICH) are used.
In EUTRA, in an uplink to transmit a signal from the mobile station apparatuses 200a to 200c to the base station apparatus 100, a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), and a physical random access channel (PRACH) are used.
LTE-A is based on the basic system of EUTRA. The frequency band used in a common system is continuous. In contrast, it has been proposed in LTE-A to operate a system by using a plurality of continuous or non-continuous frequency bands (hereinafter, “carrier component” or “component carrier (CC)”) multi-functionally as one wide frequency band (a system band having a wide band) that is called, spectrum aggregation or carrier aggregation. One system band is configured by a plurality of component carriers each of which has a part of a band width of the system band that is an available frequency band. A mobile station apparatus of LTE or LTE-A can operate in each of the component carriers. It has been proposed that a frequency band used in downlink communication and a frequency band used in uplink communication have a different frequency bandwidth, respectively to more flexibly use the frequency band that is allocated to the mobile communication system.